/*
 * Copyright 2002-2010 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.util;

import java.util.Comparator;
import java.util.Map;

/**
 * Strategy interface for <code>String</code>-based path matching.
 *
 * <p>Used by {@link org.springframework.core.io.support.PathMatchingResourcePatternResolver},
 * {@link org.springframework.web.servlet.handler.AbstractUrlHandlerMapping},
 * {@link org.springframework.web.servlet.mvc.multiaction.PropertiesMethodNameResolver},
 * and {@link org.springframework.web.servlet.mvc.WebContentInterceptor}.
 *
 * <p>The default implementation is {@link AntPathMatcher}, supporting the
 * Ant-style pattern syntax.
 *
 * @author Juergen Hoeller
 * @since 1.2
 * @see AntPathMatcher
 */
public interface PathMatcher {

   /**
    * Does the given <code>path</code> represent a pattern that can be matched
    * by an implementation of this interface?
    * <p>If the return value is <code>false</code>, then the {@link #match}
    * method does not have to be used because direct equality comparisons
    * on the static path Strings will lead to the same result.
    * @param path the path String to check
    * @return <code>true</code> if the given <code>path</code> represents a pattern
    */
   boolean isPattern(String path);

   /**
    * Match the given <code>path</code> against the given <code>pattern</code>,
    * according to this PathMatcher's matching strategy.
    * @param pattern the pattern to match against
    * @param path the path String to test
    * @return <code>true</code> if the supplied <code>path</code> matched,
    * <code>false</code> if it didn't
    */
   boolean match(String pattern, String path);

   /**
    * Match the given <code>path</code> against the corresponding part of the given
    * <code>pattern</code>, according to this PathMatcher's matching strategy.
    * <p>Determines whether the pattern at least matches as far as the given base
    * path goes, assuming that a full path may then match as well.
    * @param pattern the pattern to match against
    * @param path the path String to test
    * @return <code>true</code> if the supplied <code>path</code> matched,
    * <code>false</code> if it didn't
    */
   boolean matchStart(String pattern, String path);

   /**
    * Given a pattern and a full path, determine the pattern-mapped part.
    * <p>This method is supposed to find out which part of the path is matched
    * dynamically through an actual pattern, that is, it strips off a statically
    * defined leading path from the given full path, returning only the actually
    * pattern-matched part of the path.
    * <p>For example: For "myroot/*.html" as pattern and "myroot/myfile.html"
    * as full path, this method should return "myfile.html". The detailed
    * determination rules are specified to this PathMatcher's matching strategy.
    * <p>A simple implementation may return the given full path as-is in case
    * of an actual pattern, and the empty String in case of the pattern not
    * containing any dynamic parts (i.e. the <code>pattern</code> parameter being
    * a static path that wouldn't qualify as an actual {@link #isPattern pattern}).
    * A sophisticated implementation will differentiate between the static parts
    * and the dynamic parts of the given path pattern.
    * @param pattern the path pattern
    * @param path the full path to introspect
    * @return the pattern-mapped part of the given <code>path</code>
    * (never <code>null</code>)
    */
   String extractPathWithinPattern(String pattern, String path);

   /**
    * Given a pattern and a full path, extract the URI template variables. URI template
    * variables are expressed through curly brackets ('{' and '}').
    * <p>For example: For pattern "/hotels/{hotel}" and path "/hotels/1", this method will
    * return a map containing "hotel"->"1".
    * @param pattern the path pattern, possibly containing URI templates
    * @param path the full path to extract template variables from
    * @return a map, containing variable names as keys; variables values as values
    */
   Map<String, String> extractUriTemplateVariables(String pattern, String path);

   /**
    * Given a full path, returns a {@link Comparator} suitable for sorting patterns
    * in order of explicitness for that path.
    * <p>The full algorithm used depends on the underlying implementation, but generally,
    * the returned <code>Comparator</code> will
    * {@linkplain java.util.Collections#sort(java.util.List, java.util.Comparator) sort}
    * a list so that more specific patterns come before generic patterns.
    * @param path the full path to use for comparison
    * @return a comparator capable of sorting patterns in order of explicitness
    */
   Comparator<String> getPatternComparator(String path);

   /**
    * Combines two patterns into a new pattern that is returned.
    * <p>The full algorithm used for combining the two pattern depends on the underlying implementation.
    * @param pattern1 the first pattern
    * @param pattern2 the second pattern
    * @return the combination of the two patterns
    * @throws IllegalArgumentException when the two patterns cannot be combined
    */
   String combine(String pattern1, String pattern2);

}
